Xenozoicum: a bleak future where dinosaurs roam the Earth once more. The poacher Wrench Terhune learns of the impending arrival of an ambassador from the Wassoon tribe. Fearing that the ambassador is out to get him and his gang for the crimes they committed there, Terhune decides to assassinate the ambassador. Rumours about the plot reach Jack "Cadillac" Tenrec, who races against time to find and stop Terhune. The ambassador is a woman, Hannah Dundee, and she decides to stay for a while in the city.

Hannah Dundee, the ambassador from the Wassoon tribe, meets Remfro Rynchus, who is very interested in the flying lizards called Zekes. Hannah helps Remfro to establish a Zeke colony on top of a deserted skyscraper. Governor Nock is furious, until he realizes that the reason Hannah did this was to enable the Zekes to warn the fishing boats about approaching predators.